1. Field of the Invention
This invention relates to a container capable of holding plate-like objects including angle-like objects easily in a compactly laminated state, and more particularly to a container for plate-like objects, which is suitably used to hold, for example, plate-like wastes resulting from cutting of a used fuel channel box taken out of a boiling-water nuclear reactor.
2. Description of the Related Art
In order to place the largest possible number of plate-like objects in a container, it is necessary that the plate-like objects be laminated therein as closely as possible but laminating plate-like objects in such a manner in a container cannot always be done with ease. The conventional operation for placing plate-like objects in a container will now be described taking as an example an operation for placing in a container plate-like wastes of cut pieces of a used fuel channel box taken out of a boiling water reactor.
A fuel channel box for a boiling-water reactor is a cross-sectionally square cylinder enclosing a fuel assembly (bundle of fuel rods), having a height of about 410 cm, a width of about 15 cm and a wall thickness of 2 mm and consisting of zircaloy. When a used fuel assembly is reprocessed, the fuel channel box is removed therefrom and cut along a diagonal line of a cross section thereof in the water in a waste storage pool so as to obtain angle-like or L-shaped objects 1 of about 410 cm in length shown in FIG. 4 (accordingly, one fuel channel box is divided into two angle-like objects 1).
As shown in FIG. 5, this plate-like object 1 is suspended in the water in a waste storage pool 2 from a hoist 4, which is set on a service platform 3 provided above the pool 2 so that the platform 3 can be horizontally moved. The suspended plate-like object 1 is transferred to the position in the water and above a container 5 in the pool 2 and placed therein. Needless to say, the purpose of handling the plate-like object 1 in a waste storage pool is to prevent the radiation exposure.
In order to utilize a waste storage space with a higher efficiency, it is necessary that the largest possible number of plate-like objects 1 be placed in each container 5. Accordingly, in the conventional techniques of this kind, a worker on the service platform 3 holds an elongated rod and pushes at its free end the plate-like object 1 being placed in the container 5, in such a manner that the plate-like objects therein contact each other as closely as possible. However, moving an elongated rod in the water causes the operation efficiency to lower, and it is difficult to place plate-like objects in the container compactly by this method. Therefore, by this method, only thirty pieces of plate-like objects 1 can be placed in a container of 300 mm in length and 227 mm in width.